Catheters of the generic type are known to comprise at least one lumen that is defined by the catheter wall and serves for guidance of the electrode that must be inserted in a patient's body after insertion of the catheter. Another lumen may for example serve for displacement of the catheter by a guide wire that has been applied in advance in a patient's body or for equipment of the catheter tip with a wire pull.
Catheters of the generic type are also known to have a slit- or tear-open catheter wall so that they can easily be removed from a patient's body once the electrode has been placed. EP 0 655 257 A2 shows a catheter of that type, disclosing a catheter wall with a weakening in the form of a perforation.
A current problem in these catheters resides in the torsional and buckling strength of the catheter shank and the susceptibility thereof to compression, in particular when the catheter must be bent around a small radius, which is for example the case during insertion into the arteria subclavia.
For solving these problems, the prior art teaches to provide the catheter wall with reinforcements, by the aid of which to stabilize a catheter's torsional and/or buckling strength and to counteract any undesired compression. In this context, EP 0 898 481 B1, U.S. Pat. No. 6,159,198 A and WO 99/33509 A1 disclose to place reinforcement fibers into the catheter wall. They may be individual fibers as shown in WO 99/33509 A1 and EP 0 898 481 B1, or a meshed hose as taught in U.S. Pat. No. 6,159,198 A.
Although the inserted fibers fundamentally help in the task of reinforcement, they pose some problems in particular in the manufacture of a catheter. Fundamentally, placing fiber reinforcements as a mesh or strand structure in a hose configuration is a customary method of production, however, these fiber reinforcements are hard to adapt to certain desired properties in the axial and peripheral direction. This applies in particular when the catheter is intended to be weakened for a tear line to be provided. In this context, EP 0 898 481 B1 (mentioned above) teaches a perforation line which serves for the reinforcement fibers that extend in the peripheral direction along the catheter wall to rip open only initially. Putting this step, which is outlined diagrammatically, into practice will need considerable requirements in terms of manufacture. This applies all the more to the reinforcement fibers of strongly flatly rectangular cross-sectional shape which are mentioned in the above document and which must be expected to be severed when the perforation lines are too deep.